The presently disclosed embodiments relates to a data communication system to be utilized in a direct digital marking (printing) system, namely utilizing a rotary electrical contact to serially transfer power and millions of bits of data between a controller and a novel imaging member.
There are two conventional color printing technology platforms, i.e., inkjet and xerography, and other new color printing technology platform, i.e., digital flexo or digital offset printing. Each of these color printing technology platforms have highly complex print systems, which leads to complicated print processes, high box (device) cost, and high print run cost.
New advances in nanotechnology and display technology have led to the development/discovery that a digital electric field can be created utilizing an electric field induced hole injection reaction between a patternable hole injection nanomaterial and the Xerox charge (hole) transport layer. For example, in U.S. Pat. Nos. 8,233,017 and 8,173,340 , entitled Digital Electrostatic Latent Image Generator, and Digital Electrostatic Latent Image Generator, respectively, Carbon Nanotube (CNT) and PEDOT were found to inject holes efficiently to the Xerox charge transport layer (CTL, TPD in polycarbonate) under the influence of an electric field. CNT and PEDOT are patternable using nanofabrication techniques and thus pixels can be made in the micron dimension. When these pixels are overcoated with the TPD CTL, digital latent images may be created and these pixels may be integrated into the appropriate backplane technology to fully digitize the printing system.
In addition, in a xerographic development system, latent image generation and toner development can also occur without using the conventional combination of the ROS/ Laser and charger thus simplifying the generation of latent electrostatic images compared to xerography. This has been discussed in application Ser. No. 12/869,605, entitled “Direct Digital Marking Systems.” Illustratively, a bilayer device comprising a PEDOT hole injection layer and the TPD CTL may be mounted an OPC drum in the CRU. The drum was rotated through the development nip and a toner image was observed in the post-development region. As the bilayer member first contacted the magnetic brush, the bias on the magnetic brush induced a hole injection reaction to create the electrostatic latent image on the CTL surface of the bilayer. This was followed by toner development before the bilayer member exited the development nip. This two step process was accomplished within the development nip, resulting in direct toned printing without laser/ROS, charger or PR. The permanent image may be obtained by transferring the toned image to paper following fusing.
This nano image marker and the direct digital printing process can also be extended to print with flexo ink, offset ink and liquid toner, as is discussed in application Ser. No. 12/854,526, entitled “Electrostatic Digital Offset Printing.” Thus, the new direct printing concept may be regarded as a potential new digital printing platform.
U.S. Pat. No. 6,100,909 (to inventors Hass and Kubby) describes an apparatus for forming an imaging member. The apparatus includes an array of high voltage thin-film transistors (TFT) and capacitors. A latent image is formed by applying DC bias to each TFT using a High Voltage Power Supply and charged-area detection (CAD)-type development. FIG. 1 illustrates an array of thin film transistors in the apparatus for forming an imaging member. The array 10 is arranged in a rectangular matrix of 5 rows and 5 columns. Although only five rows and columns are illustrated, in embodiments of the invention located in devices that print or image on an 8.5 inch by 11-inch array having a 600 dots per inch (dpi) resolution, the array 10 would include 3×105 transistors which would correspond to 3×105 million pixel cells. In addition, for 1200 dpi resolution, the array would have 7×105 million transistors and 7×105 pixel cells.
The array 10 when coupled to a bilayer imaging member consisting of hole injection pixels overcoated with a hole transport layer generates latent images from digital information supplied by a computer 44 (e.g., print engine) to a controller 42. The computer supplies digital signals to a controller 42 (or a digital front end (DFE)), which decompose the digital signals into the utilized color space (e.g., either CMYK or RGB color space) with different intensities and the digital bits are created that correspond to the image to be printed. The controller 42 directs the operation of the array 10 through a plurality of interface devices including a decoder 12, a refresh circuit 18, and a digital-to-analog (D/A) converter 16
In contrast to other active matrix products (such as a television or monitor), which are static, the new nano imaging member (whether connected to or part of a belt or drum) is expected to be moving during the printing process. Millions of bits will need to be transmitted to the moving imaging member to create the digital electric filed. The moving imaging member is attached a rotating imaging drum. In addition, power needs to be supplied to the driving electronics and moving imaging member. Thus, a serious challenge arises to commutate the backplane with the driving electronic while the belts (or drum) are moving. While the belt or drum is moving, millions of bits and also electric current are being supplied to the backplane. The data needs to be transmitted and received in the high Megahertz range in order to meet customer needs.
In prior filed application entitled Generation of Digital Electrostatic Latent Images Utilizing Wireless Communications, Attorney Docket No. 20101021-390426, it was proposed to transmit the data wirelessly from the controller to the imaging drum. This implementation requires an extra level of hardware which is the wireless transmitter and receiver (i.e., the wireless link). This increases the costs of the printing device. In addition, depending on the wireless transmission protocol utilized, security may be an issue because the wireless transmission may not be secured or encrypted.
In addition, connecting the millions of transistors in the array, which is attached to a rotating drum, is difficult. Brushes and other types of contacts, which are normally utilized, are problematic due to the large number of brushes (or contacts) that are required. The noise created by the brushes or other contacts can cause errors in data transmission accuracy.
Accordingly, there is an unmet need for systems and/or methods that provide the large amount of data to the moving nano imaging member in a printing device in an accurate and cost-effective manner. The data needs to be transferred via a minimum number of contacts between the controller and the rotating drum (array).